Simplify DDNS flow and polish UI

router_dyndns/routers/management_shared.py

@@ -78,7 +78,6 @@ async def render_management_page_async(
     account: ManagementAccount,
     csrf_token: str,
     message: str | None = None,
-    challenge: dict[str, str | None] | None = None,
     created_account: dict[str, str] | None = None,
 ) -> str:
     return await run_in_threadpool(
@@ -89,7 +88,6 @@ async def render_management_page_async(
         account,
         csrf_token,
         message,
-        challenge,
         created_account,
     )